Lubrication of rotary valves



p 19424 F. M. ASPIN 2,296,081

LUBRICATION OF ROTARY VALVES Filed Dec. 28, 1940 2 Sheets-Sheet l IIIIIIII----4,.

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" Sept. 15, 1942. I F. M. ASPIN 2,296,081

LUBRICATION. 0F ROTARY VALVES Filed Dec. 28, 1940 2 Sheets-Sheet 2 Patented Sept. 15, 1942 LUBRICATION OF ROTARY VALVES Frank Metcalf Aspin, Bury, England Application December 28, 1940, Serial No. 372,063 In Great Britain December 9, 1939 8 Claims.

This invention relates to the lubrication of rotary valves and is particularly applicable to ro tary valves for internal combustion engines of the kind described in the specifications of applicants copending applications 89,115, filed July 6, 1936, now Patent 2,283,594 granted May 1%, 1942, and 258,224, filed Feb. 24, 1939, now Patent 2,245,743, granted June 14, 1941, though not limited to such application.

One of the main problems with rotary valves is their lubrication to obtain at the same time efiicient and economical lubrication. This problem is inherent in the design of any rotary valve because a substantial portion of the valve surface which has to be lubricated to provide a bearing surface or gas seal, also has to pass the port or ports where loss of lubricant may occur.

The object of the invention is an improved method of and means for lubricating a rotary valve both efiiciently and economically.

The invention comprises the method of lu brication of a rotary valve wherein an oil film is maintained between the co-acting bearing or gas-sealing surfaces of the valve member and its ported seating and wherein part, at least, of

such oil film is diverted from that part of the surface of the rotary valve member where and before it passes the port or ports.

According to the invention, means are provided for establishing an oil film at the co-acting bearing or gas-sealing surfaces of the rotary valve member and its seating in combination with means, adjacent to the port or ports in the valve seating, for removing at least a substantial part of the oil film from that part of the surface of the rotary valve member where and before it passes the port for re-establishing the oil film thereon immediately after passing the port.

The accompanying drawings illustrate one example of the invention, in which Fig. 1 is a perspective axial section of the valve housing;

Fig. 2 is a perspective View of the lower part of the rotary valve member;

Fig. 3 is a cross section on line 33 of Fig. 2,

Fig. 4 is a cross section on line 4@ of Fig. 1;

Fig. 5 is a part section on line i-5 of Fig.1;

Figs. 6 and 7 show modifications of the invention.

In the example of the invention illustrated in the drawings, a rotary valve member and its housing constructed in accordance with the specification of the applica'nts U. S. Patent No. 2,283,594, the valve member has a conical peripheral face Iii seating directly in a conical face II in the housing, These coacting faces may, if of suitable material and proportions, form the bearing taking the whole of the thrust load on the valve member. On the other hand, supplementary anti-friction thrust bearings may be provided in accordance with the U. S. Patent No. 2,245,743.

The rotary valve member, at its smaller conical end, merges into a cylindrical shaft or extension l2 in which are formed two piston ring grooves I3, the duty of which rings is to retain any oil film on the conical surfaces and to prevent such oil from escaping up the valve shaft [2. The tapered face I!) of the valve member is longer than the depth of the port Id of the valve by a suitable amount necessary to provide a bearing and gas seal, and in the particular example herewith described such face Ill is in all approximately 3 inches long measured down its sloping face, whilst the port I4 is of such depth as to leave a conical portion at I 5 of about inch length above the port and of about 1% inch length at l6 below the port, i. e. at the larger diameter of the valve member,

Wavy oil grooves I! and I8 are formed on the face ll] of the rotary member in the centre of these continuous conical portions, the amplitude of the wave being approximately half the length of the conical space. The pitch of the upper wavy groove I1 is about inch, whilst that of the lower wavy groove I8 is about 1 inches. These grooves are only shallow and may conveniently be formed by cam turning. The proportion of the groove is therefore such that it sweeps an area approximately half the complementary continuous bearing surface area of the housing beyond the ends of the port.

The valve housing has two ports, see Fig. 4, one [9 for the inlet and the other 22 for the outlet. Four oil grooves, 21a, 21b, 2lc and 21d (see Figs. 1 and 4) are formed in the conical face of the seating on each side of the ports and extending into the vicinity of the region supplied by the wavy oil grooves I1 and It in the rotary member. These grooves Zia, Zlb, 21c and 2id are spaced a short distance away from the port side say about inch, and are shaped so that their edges immediately adjacent to the ports are sharp and radial or normal to the surface whilst their other edges away from the ports are sloped or bevelled. The arrow shows the direction of rotation of the rotary member. The trailing edges 22 and 23 of the ports are rounded off (see Fig. 4) whilst the leading edges 24 and 25 are preferably angular as shown.

Oil ducts 26 (see Figs. 4 and 5) are provided in the wall of the housing in the vicinity of the wavy grooves on the rotary member, and to which oil is fed under low pressure to reach the said wavy grooves.

In operation, the oil supplied under low pressure to the ducts 26, in the housing is picked up by the wavy grooves and distributed effectively over the continuous conical portions l5 and I6 respectively above and below the port. The oil also spreads from such area into the grooves on each side of the ports and is particularly carried to the groove 2 la on the far side of the port. The oil fills the full length of the groove and spreads therefrom to the intervening conical portion of the co-acting conical surfaces assisted by the shaping or inclining of the back edge of the groove. When such oil film reaches the grooves Zla and He in front of the ports a substantial part of the film is scraped from the rotary member by the combined action of the reverse action and the sharp facing edge of such groove, and is led by such groove to the ends where it supplements the oil film and passes round the upper and lower ends of the port from where it enters the ends of the next groove beyond the port and spreads along the same, filling it and spreading out therefrom by groove action to cover the intervening conical portion of the rotary member.

Communicating grooves 21 (see Fig. 6) may be provided in the housing joining the ends of the side grooves Zlc and 21d arranged above and below the port so as to help carry the oil round the port as above described.

As shown in Fig. 7 additional grooves 28 are provided in the housing as an extension of the ends of the leading side groove Zld to the areas above and below the port so that they fade out gradually in such areas and thus operate directly to increase the oil film supply pressure in such areas.

The side grooves 2la, Zlb, 210 and 2ld in the housing may be straight down the inclined face parallel with the sides of the ports as shown in Fig. 1 or may be curved or inclined and there may be two or more grooves relatively close together as may be found to be desirable. The combination of the effectively lubricated zones above and below the ports and particularly below the ports and the distributing grooves at the sides of the ports'can be used effectively to maintain lubrication for the whole co-acting conical bearing surfaces with very little loss at the ports, an effect hitherto unobtainable. Lubrication of the end portions of the conical bearing surfaces and particularly the lower portion which is a danger zone can always be effectively maintained at the same time. Incidentally, it has been found that the collection of carbon in the lubricating grooves does not prejudice or does not in practice occur to such an extent as to prejudice the efficient operation of the improved system of lubrication.

The invention is obviously not limited to all the details of construction of the example above described as the same may be modified without departing from the nature of the invention. For example, lubricant holding grooves may be provided in the valve housing instead of, or in addition to the grooves l1 and [8 in the rotary valve member and such grooves may be similarly wavy and continuous.

What I claim is:

1.-A valve comprising a valve housing forming a socket, a plug rotating in the socket, said socket and plug having lubricated complementary engaging surfaces with complementary ports therein forming in such surfaces zones disposed in the direction of rotation, said zones respectively being interrupted and uninterrupted by said ports, means for continuously lubricating said surface zones not interrupted by the ports, said interrupted surface zone of the socket having a groove formation arranged across the direction of relative movement of the plug surface and with a relatively vertical wall facing the lubricant carried on the approaching surface of the plug and a relatively inclined wall down which the lubricant can spread as it enters the groove formation, whereby said groove formation is adapted to interrupt some part of the lubricant n that portion of the plug immediately before such lubricant reaches the port in the socket.

2. A valve comprising a valve housing forming a socket, a plug rotating in the socket, said socket and plug having lubricated complementary engaging surfaces with complementary ports therein forming zones in such surfaces disposed in the direction of rotation, said surfaces respectively being interrupted and uninterrupted by said ports, means for continuously lubricating said surface zones not interrupted by the ports, said socket having in its interrupted surface zone a groove formation arranged across the direction of relative movement of the plug surface and with a relatively vertical wall facing the lubricant carried on the approaching surface of the plug and a relatively inclined wall down which the lubricant can spread as it enters the groove formation, whereby said groove formationi is adapted to interrupt some part of the lubricant on that portion of the plug immediately before such lubricant reaches the port in the socket and said socket being provided with a further groove formation to restore the interrupted lubrication immediately beyond the port in the socket.

3. A valve comprising a valve housing forming a socket, a plug rotatin in the socket, said socket and plug having lubricated complementary engaging surfaces with complementary ports therein forming zones in said surfaces disposed in the direction of rotation, said zones respectively being interrupted and uninterrupted by said ports, means for continuously lubricating said surface zones not interrupted by the ports, said socket having in its interrupted surface zone a groove formation arranged across the direction of relative movement of the plug surface and with a relatively vertical wall facing the lubricant carried on the approaching surface of the plug and a relatively inclined wall down which the lubricant can spread as it enters the groove formation, whereby said groove formation is adapted to interrupt some part of the lubricant on that portion of the plug immediately before such lubricant reaches the port in the socket, said socket having a further groove formation arranged to restore the interrupted lubrication immediately beyond the port in the socket, said further groove formation having relatively vertical and inclined walls similar to the first named groove formation but oppositely directed.

4. A valve comprising a valve housing forming a socket, a plug rotating in the socket, said socket and plug having lubricated complementary engaging surfaces with complementary ports therein forming zones in such surfaces disposed in the direction of rotation, said zones respectively being interrupted and uninterrupted by said ports, means for continuously lubricating said surface zones not interrupted by the ports, said socket having in its interrupted surface zone a grooveformation arranged across the direction of relative movement of plug surface and with a relatively vertical wall facing the lubricant carried on the approaching surface of the plug and a relatively inclined wall down which the lubricant can spread as it enters the groove formation, whereby such groove formation is adapted to interrupt some part of the lubricant on that portion of the plug immediately before such lubricant reaches the port in the socket and said socket being provided with a further groove formation to restore the interrupted lubrication immediately beyond the port in the socket and having inclined walls similar to the first named groove formation but oppositely directed and extending into said interrupted zone of the surface of the socket.

5. A valve comprising a valve housing forming a socket, a plug rotating in the socket, said socket and plug having lubricated complementary engaging surfaces with complementary ports therein forming zones in said surfaces disposed in the direction of rotation and said zones respectively being interrupted and uninterrupted by said ports, means for continuously lubricating the said surface zones not interrupted by the ports and said socket having a groove formation in its interrupted surface zone arranged across the direction of relative movement of the plug surface and with a relatively vertical wall facing the lubricant carried on the approaching surface of the plug and a relatively inclined wall down which the lubricant can spread as it enters the groove formation, whereby such groove formation is adapted to interrupt some part of the lubricant on that portion of the plug immediately before such lubricant reaches the port in the socket and said socket being provided with a further groove formation to restore the interrupted lubrication immediately beyond the port in the socket, said further groove formation having inclined walls similar to the first named groove formation but oppositely directed,

extending into said uninterrupted zone of the surface of the socket in the direction of the rotation of the plug surface.

6. A valve comprising a valve housing forming a socket, a plug rotating in the socket, said socket and plug having lubricated complementary engaging surfaces with complementary ports therein forming zones in such surfaces disposed in the direction of rotation, said zones respectively being interrupted and uninterrupted by said ports, means for continuously lubricating said surface zones not interrupted by the ports and said socket being provided in its interrupted surface zone with a groove formation arranged across the direction of relative movement of the plug surface and with a relatively vertical wall facing the lubricant carried on the approaching surface of the plug and a relatively inclined wall down which the lubricant can spread as it enters the groove formation, whereby said groove formation is adapted to interrupt some part of the lubricant on that portion of the plug immediately before such lubricant reaches the port in the socket and said socket being provided with a further groove formation to restore the interrupted lubrication immediately beyond the ports in the socket, said further groove formation having inclined Walls similar to the first named groove formation but oppositely directed and extending into said interrupted zone of the surface of the socket in the direction of rotation of the plug surface, said last named directional portion of the groove formation tapering towards its ends.

'7. A valve comprising a valve housing having a socket, a plug rotating in the socket, said socket and plug having lubricated complementary engaging surfaces with complementary ports therein forming zones in such surfaces disposed in the direction of rotation, said zones respectively being interrupted and uninterrupted by said ports, means for continuously lubricating said surface zones not interrupted by the ports, said socket being provided in its interrupted surface zone With a groove formation arranged across the direction of relative movement of the plug surface and with a relatively vertical wall facing the lubricant carried on the approaching surface of the plug and a relatively inclined wall down which the lubricant can spread as it enters the groove formation, whereby such groove formation is adapted to interrupt some part of the lubricant on that portion of the plug immediately before such lubricant reaches the port in the socket, the means for lubricating said uninterrupted zone comprising a continuous groove in the surface of the plug located above and below said port.

8; A valve comprising a valve housing having a conical ported socket, a conical ported plug rotating in the conical ported socket, said socket an lug having complementary engaging surfaces, said plug having in its surface a continuous groove located above and below the ports for affording, continuous lubrication in those areas, and said socket having a continuous groove around each port, those parts of the groove of the socket immediately in advance of the ports being shaped with a steep and inclined wall, the former facing the lubricant as it is carried around on the plug so as to scrape it off into the groove, those parts of the groove immediately in rear of the ports being similarly shaped and arranged in reverse disposition so that the inclined wall forms with the plug a wedge shaped space converging in the directionof rotation to cause lubricant to be drawn out of the groove by the plug and the intermediate parts of the groove serving to conduct the lubricant scraped off'the plug by the first mentioned parts of the groove to the second mentioned parts of the groove.

RANK METC'ALF ASPIN. 

